Magneto



Dec. 5, 1933. E, F WESTON t 1,937,677

MAGNETC Filed Aug. 5, 1931 l ipignl X ,l L..

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Patented Dec. 5, 1933 UNl'rsDsTA'n-:s PATENT ori-"1ct:

MAGNETO Edward F. Weston, Newark, N. J., assignor to Weston Electrical Instrument Corporation, Newark, N. J., a corporation of New Jersey Application August 5, 123i. seriei'No. 555,295

1o claimt. (01471-209) l0 nected that the assembly, repair and/or replacement of parts is facilitated. An object is to provide a magneto in which all of the electrical and magnetic parts are assembled upon and carried by a base plate, and the casing which supports and houses the assembly may be connected to or removed from the base plate without disturbing the assembly. A further object is to provide a magneto of the `rotating magnet type which includes a satisfactory, rugged support for l0 the rotating magnet. More specifically, an object is to provide an armature and circular magnet assembly in which a shell carries the magnet and encloses the assembly, and in which the armature shaft extends through one end of the shell and the opposite end of the shell carries a second shaft, one of said shafts serving to support the assembly while the other serves as the drive for therotatlng element of the magneto.

i These and other objects of the invention will be apparent from the following specification and the accompanying drawing in which: Fig. 1 is a central longitudinal section taken through one embodiment of the invention, Fig. 2 is an end view of the same, and Fig. 3 is a transverse section taken substantially on line 3-3 of Fig. 1. In the drawing, the numeral 1 identines the main section of the casing, which preferably takes the form of a cylinder having one end 2 of reduced diameter that is internally threaded for connection to the sleeve which houses the tachometer drive shaft of an airplane or other engine, this reduced diameter section being split longitudinally and provided with a clamp bolt 3 for locking the magneto casing to the engine structure.

The end plate 4 closes the open end of the casmg 1 and is seemed thereto by bolts 5 that engage the thickened rim at the open end of the 5 tubular casing'. The end`plate 4 is preferably formed of a molded synthetic resin and has a central aperture for receiving the end of the rod orshaftthatsupportsbotharmature andmagnet structures. The laminated armature?. is se- .55 cmodpontne siutrttsanumoybeor'theeon-4 `ventional designwith longitudinal slots to receive the windings 8.

Shaft 6 has a radial flange 9 that engages the inner race of a ball bearing 10 to clamp the bearing against the inner face of the end plate 4 6 when the nut 11 is threaded upon the outer end of shaft 6 to secure the shaft to the armature endplate. A second bearing 12 is secured to the opposite end of shaft 6 by a bushing 13, and the outer races of the bearings carry the circular 05 magnet 14 through the supporting frame or shell ,15. vThe magnet is laminated and the stampings are held together by bolts 16.and nuts 17. the bolt ends projecting well beyond the umagnet laminationsto receive nuts 18 which clamp the 70 shell 15 to the magnet. The shell is formed in two sections which preferably meet approximately at the longitudinal center of the magnet and the ends of the shell are of reduced diameter to fit snugly upon the bearings 10, 12, and are provided with inturned flanges 19, 20. The flange 19 adjacent the end plate 4 is seated against the outer race of bearing 10, and the flange 20 is spaced from bearing 12 and carries a plate 21 to which the coupling shaft 22 is secured. The 9 shaft 22 has a key or projecting rib 23 for ensagement with the form oftachometer drive shaft construction that is customarily employed on airplane engines, and the shaft lies within the. sleeve 2 of the casing in such position that the 95 driving connection is established when the magnetocasing is secured to the engine casing by the sleeve 2. A flexible guard 24 is mounted in the sleeve extension 2 to prevent oil, dust or other foreign matter from entering the casing about the shaft 22. As stated above, the end plate 4 preferably comprises a molded body of synthetic .resin as this construction permits the Shanks of the magneto terminals 25, 26 to be secured to the end 95 plate during the molding operation. The leads 27 from the armature winding 8 are brought through the end plate through a slot 28 in the shaft 6, and are connected to the respective terminals 25, 26. The terminals extend through a cover plate 29 and carry nuts 30 which hold the cover plate in place, a gasket 31 being preferably arranged between the cover plate 29 and the end plate 4 to provide a dustproof closure for the outer end of the magneto structure.

The construction is particularly advantageous from the standpoint of assembly, testing and repair or replacement. The end plate provides a cantilever support for the armature shaft 6 which carries the :amature-magnet system, and. 11

and tested before the casing 1 and cover plate 29 are in place. The identical magneto assembly may therefore be housed in other types of casings, they design of the casing and of the coupling shaft 22 being varied in accordance with the nature of the structure upon which the magneto is to be mounted and the type of rotating system which is to operate the magneto.

.I claim:

'1. In a magneto, a casing, an armature within said casing, a shaft rigidly connecting said armature and casing, a winding on said armature, a magnet within said casing and surrounding said armature, bearings carried by said shaft at opposite ends of said armature, means rotatably supporting said magnet on said bearings, a coupling ,shaft connected to said magnet supporting means, and means on said coupling shaft adapted to connect the same to a power source outside of said casing.

2. The invention as set forth in claim 1, wherein said casing comprises a plurality of sections, and said armature shaft is connected to only one of said sections.

3. The invention as set forth in claim l, wherein said casing comprises a plurality of sections,

and one of said sections terminates in a sleeve for mounting said magneto on a supporting structure, said coupling shaft being positioned within said sleeve.

4. In a magneto, a tubular casing having one end provided with means for securing the casing to a support, a shaft secured to the opposite end of and extending axially of said casing,` a frame having the opposite ends thereof rotatably supported on said shaft, means preventing axial displacement of said frame on said shaft, a magnet carried by said frame, and a winding supported by said shaft within said magnet.

.5. The invention as set forth in claim 4, where-- in said frame comprises a shell completely enclosing said magnet and Winding.

6. In a magneto, a casing 'comprising sectionsmeeting on a plane normal to the a'xis of the casing, a shaft secured to one of said sections and extending substantially through the space within said casing, a frame Yhaving the opposite ends thereof rotatably supported on said shaft, a magnet carried by said frame, an armature on said 'shaft within said'frame, and a winding on said armature.

7. The invention as set forth in claim 6, where-Y the end of said shell. at the end thereof remote from the supported end of said shaft.

8. The invention as set forth in claim 6, wherein the casing section not supporting said shaft terminates in 'a sleeve for securing said magneto to a supporting structure, and means in said sleeve and connected to said shell for rotating the same.

9. In a magneto, a tubular casing having an open end, an end plate closing the said open end of said casing, a shaft supported by said end plate, an armature on said shaft, a winding on said armature, a circular magnet surrounding said armature, a frame carrying said magnet, and means rotatably supporting the outer ends "of said magnet frame on said shaft.

- combination with a coupling shaft secured to the open end, a closure for said open end, a shaft xed to said closure, an armature and armature windingl carried by said shaft, a circular magnet surrounding said armature, and a transversely split shell secured to said magnet and substantially enclosing said magnet and armature, said shell having end portions of reduced diameter rotatably supported on said shaft.

11. The invention as set forth in claim 10, in v end of said shell remote from said casing closure, the end of said casing adjacent said coupling shaft being of reduced diameter and carrying a dust guard through which said coupling shaft projects.

12. In a magneto, an armature having a winding thereon, a shaft carrying said armature, bearings having the inner races thereof supported on said shaft adjacent the ends thereof, a circular magnet, and a split shell supporting said magnet and enclosing said armature, said shell having end portions of reduced diameter within which the outer races of said bearings are seated.

13. The invention as set forth in claim 12, wherein the reduced diameter portion of one end of said shell is internally flanged, a plate secured to said flange, and a coupling shaft secured to nsaid plate.

14. In a magneto, the combination with a substantially rigid assembly comprising an end plate, a shaft having one end thereof secured to and axially of said plate, and an armature and armature winding xed upon said shaft, of a circular magnet surrounding said armature, means rotatably supporting said magnet on said shaft,

a casing open at both lends, said casing being secured tosaid end plate and with the end plate closing one end of said casing, and a coupling shaft within said casing and secured to said magneto, said coupling shaft being accessible through the other open end of said casing.

15. The invention as set forth in claim 14, wherein said supporting means includes a shell secured to said magnet and enclosing said armature.

16. The invention as set forth in claim 14, in combination with means at the end of said casing opposite said end plate for securing said casing to a support.

17. In a magneto, a casing, a plate closing 125 one end of said casing, a shaft secured to said plate, an armature and armature winding on said shaft, a magnet -rotatably supported by said shaft, terminals for said winding and carried 1 by said plate, and a cover secured to said plate, said coverbeing apertured for the passage therethrough of said terminals.

18. In a -magneto,k the combination with a plate, an armature and winding supported from ing, mounting means for said magnet and supported from said plate, and terminals carried by said plate and connected to said winding, of a casing secured to said plate and enclosing said winding and magnet, and means on said casing for securing said magneto to a supporting structure. A

19. The invention as set forth in claim 18, wherein one end only of a shaft is secured to said end plate, and said shaft carries said arma.- ture, said windings, and bearings supporting said magnet. EDWARD F. WESTON. 

